From 20e8297768cec6b9eae229272dead5d873624217 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Mon, 30 Jul 2012 16:31:51 +1000
Subject: [PATCH] Add query for decimal digits of an integer

---
 maths.cpp | 18 ++++++++++++++++++
 maths.hpp |  4 ++++
 2 files changed, 22 insertions(+)

diff --git a/maths.cpp b/maths.cpp
index 2d9cc7fc..5ae25e7e 100644
--- a/maths.cpp
+++ b/maths.cpp
@@ -65,6 +65,24 @@ template bool is_integer (const double&);
 template bool is_integer (const  float&);
 
 
+//-----------------------------------------------------------------------------
+template <>
+unsigned
+digits (const uint32_t &v) {
+    return (v >= 1000000000) ? 10 :
+           (v >=  100000000) ?  9 :
+           (v >=   10000000) ?  8 : 
+           (v >=    1000000) ?  7 :
+           (v >=     100000) ?  6 :
+           (v >=      10000) ?  5 : 
+           (v >=       1000) ?  4 :
+           (v >=        100) ?  3 :
+           (v >=         10) ?  2 :
+                                1;
+}
+
+
+//-----------------------------------------------------------------------------
 template <>
 bool
 almost_equal (const float &a, const float &b)
diff --git a/maths.hpp b/maths.hpp
index a15d210d..3653e824 100644
--- a/maths.hpp
+++ b/maths.hpp
@@ -55,6 +55,10 @@ bool
 is_integer (const T& value) pure;
 
 
+template <typename T>
+unsigned
+digits (const T& value) pure;
+
 
 /**
  * Check if two floating point numbers are approximately equal. Returns true